Low Temperature Physics

Green’s function method to the ground state properties of a two-component Bose–Einstein condensate

Chen Liang, Kong Wei, B. J. Ye, H. M. Wen, X. Y. Zhou, Rong Dian Han

Published Jul 1, 2011• 1 citation

Abstract

The elementary excitation spectrum of a two-component Bose–Einstein condensate is obtained by Green’s function method. It is found to have two branches. In the long-wave limit, the two branches of the excitation spectrum are reduced to one phonon excitation and one single-particle excitation. With the obtained excitation spectrum and the Green’s functions, the depletion of the condensate and the ground state energy have also been calculated in this paper.

DOI: 10.1063/1.3633685

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